Unit 2 AP Psychology

Peripheral nervous system (PNS)

the sensory and motor neurons that connect the central nervous system to the rest of the body

threshold

the level of stimulation required to trigger a neural impulse. When neuron reaches 55 mv it goes into depolarization

all-or-nothing response

a neuron's reaction of either firing or not firing.

synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap or synaptic cleft.

neurotransmitters

chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, they travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

reuptake

a neurotransmitter's reabsorption by the sending neuron.

endorphins

"morphine within"—natural, opiate-like neurotransmitters linked to pain control and to pleasure.

Agonist

A chemical that mimics the action of a neurotransmitter.

Antagonists

Chemical substances that block or reduce a cell's response to the action of other chemicals or neurotransmitters.

nervous system

the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.

Central nervous system (CNS)

the brain and the spinal cord

biological psychologists

the scientific study of the links between biological and psychological processes.

neuron

a nerve cell; the basic building block of the nervous system.

dendrites

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body.

axon

the neuron extension that passes and electrical messages through its branches to other neurons or to muscles or glands.

myelin sheath

a layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

action potential

a neural impulse; a brief electrical charge that travels down an axon.

refractory period

a period of inactivity after a neuron has fired.

nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs.

sensory (afferent) neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord.

motor (efferant) neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands.

interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs.

Somatic nervous system

the division of the peripheral nervous system that controls the body's skeletal muscles (skeletal nervous system)

Autonomic nervous system

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs. It's sympathetic system arouses and parasympathetic calms.

Sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations. (If you get scared)

Parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy (Your PARents come home and calm you down)

Reflexes

simple, automatic responses to sensory stimuli, such as the knee-jerk response

Endocrine system

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

Hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

Adrenal glands

a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress

Pituitary gland

"THE MASTER GLAND" the endocrine system's most influential gland

under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands

Lesion

tissue destruction. It can occur naturally or experimentally by the caused distruction/remove of brain tissues

Electroencephalogram (EEG)

An amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp.

CT (computed tomography) scan

a series of x-ray photographs taken from different angles and combined by computer into a composite representaion of a slice through the body. Aslo called a CAT scan

(PET) Positron emission tomography scan

A visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task.

MRI (magnetic resonance imaging)

a TECHNIQUE THAT USES MAGNETIC FIELDS AND RADIO WAVES TO PRODUCE COMPUTER generated images that distinguish among different types of soft tissues.

fMRI (functional MRI)

A technique for revealing bloodflow and, therefore, brain activity by comparing successive MRI scans. fMRI scans show brain function.

Brainstem

the oldest part and central core of brain. AKA reticular formation, or reticular activating system. In charge of automatic survival functions

Medulla

The base of the brainstem. Controls heartbeat and breathing.

Pons

sleep and arousal

Thalamus

the brains 'sensory switch board' Located at top of brainstem; directs messages to the sensory areas and transmits them to cerebellum and medulla.

Reticular Formation

Plays an important role in controlling arousal.

Cerebellum

"little brain" at the rear of the brainstem; functions including processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory.

Limbic system

A system of neural structures at the border of brainstem. Associated with emotions like fear, agression, and drives such as those for food and sex. Includes the Hippocampus, Amygdala and hypothalamus.

Amygdala

2Lima bean sized neural clusters in the limbic system, linked to emotion. Includes rage and fear.

Hippocampus

Limbic system. Learning and memory matcher.

hypothalamous

A neural structure lying below the thalamus, it directs several maintenance activities (eating, drinking, body temperature) helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.

Cerebral cortex

Fabric of interconnected neuron cells. Higher order thinking. Takes meaning and puts it to focus. The body's ultimate control and information-processing center.

Glial Cells

Cells in the nervous system that support, nourish, and protect neurons.

Frontal Lobes

the portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgements.

Parietal lobes

The portion of the cerebral cortex lying at the top of the head and toward the rear; includes the sensory cortex. Receives sensory input for touch and body position.

Occipital lobes

the portion of the cerebral cortex lying at the back of the head; includes the visual areas, which receive visual info from the opposite visual feild.

Temporal lobes

The portion of the cerebral cortex lying roughyl above the ears; includes the auditory areas, each of which revieves aditory info primarily from the opposite end.

motor cortex

an area at the rear of the frontal lobes that controls voluntary movements.

somatosensory cortex

the area at the front of the parietal lobes that registers and processes body touch and movement sensations.

association areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

Plasticity

The brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience.

Neurogenesis

Formation of new neurons

Corpus Callosum

Large band of neural fibers connecting the two brain hemispheres and carrying messages between them.

Split Brain

A conditioning resulting from surgery that isolates the brain's two hemispheres by cutting the fibers connecting them.

Cognitive Neuroscience

The interdisciplinary study of the brain activity linked with cognition. (including perception, thinking, memory and language.)

behavior genetics

the study of the relative power and limits of genetic and environmental influences on behavior

environment

every nongenetic influence, from prenatal nutrition to the people and things around us, Every nongenetic influence, from prenatal nutrition to the people and things around us.

chromosomes

threadlike structure made of DNA molecules that contain the genes

DNA (deoxyribonucleic acid)

(deoxyribonucleic acid) a complex molecule containing the genetic information that makes up the chromosomes

genes

the biochemical units of heredity that make up the chromosomes; segments of DNA capable of synthesizing a protein

genome

the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes

identical twins (monozygotic)

twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms

fraternal twins (dizygotic)

twins who develop from separate fertilized eggs; no genetically closer than brothers and sisters, but they share a fetal environment

molecular geneticists

subfield of biology that study the molecular structure and function of genes

heritability

the proportion of variation among individuals that we can attribute to genes; this may vary depending on population range and the environment being studied

interaction

the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)

epigenetics

The study of environmental influences on gene expression that occur without a DNA change.

evolutionary psychologists

The study of the evolution of behavior and the mind, using principles of natural selection.

natural selection

the principle that, among range of inherited trait variations, those that lead to increased reproduction and survival will most likely be passed on to succeeding generations

mutations

A random error in gene replication that leads to a change

Soma

cell body of a neuron

Nodes of Ranvier

Gaps in the myelin sheath to which voltage-gated sodium channels are confined.

Terminal Buttons

Small knobs at the end of axons that secrete chemicals called neurotransmitters

receptor sites

Locations on a receptor neuron into which a specific neurotransmitter fits like a key into a lock.

resting potential of a neuron

its stable, negative charge when the cell is inactive

Leak Channels

channels that are always open and allow ions to move along their gradient

excitatory neurotransmitters

chemicals released from the terminal buttons of a neuron that excite the next neuron into firing

inhibitory neurotransmitters

inhibit the next cell from firing

Acetylcholine (ACh)

A neurotransmitter that enables learning and memory and also triggers muscle contraction

GABA (gamma-aminobutyric acid)

A major inhibitory neurotransmitter. Undersupply linked to seizures, tremors, and insomnia.

Glutamate

A major excitatory neurotransmitter; involved in memory. Most common neurotransmitter

Norepinephrine (Noradrenaline)

Neurotransmitter active in the central and peripheral nervous systems, controlling heart rate, blood pressure, and respiration, among other functions. Because of its role in the body's alarm reaction, it may also contribute generally and indirectly to panic attacks and other disorders.

Neuroplasticity

the ability within the brain to constantly change both the structure and function of many cells in response to experience or trauma

Seratonin (5-HT)

Excitatory or inhibitory; involved in sleep, mood, anxiety, and appetite. Can lead to depression when levels are low.

Dopamine (DA)

Excitatory or inhibitory; involved in control of movement and sensations of pleasure.

glands of the endocrine system

release hormones into the bloodstream

Adrenocorticotropic hormone (ACTH)

stimulates the adrenal cortex

Thyroid Gland

produces hormones that regulate metabolism, body heat, and bone growth

Pancreas

Regulates the level of sugar in the blood and produces insulin

Gonads

ovaries and testes

Hindbrain

medulla, pons, cerebellum

Midbrain

Region between the hindbrain and the forebrain; it is important for hearing and sight. Consists of Tectum and Tegmentum

Forebrain

The largest and most complicated region of the brain, including the thalamus, hypothalamus, limbic system, and cerebrum.

Limbic System

neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives.